The use of oxygen for treatment of open wounds and sores has long been understood to have practical medical application as a supplement or replacement to conventional antibiotic therapy. Oxygen is believed to be bactericidal to the anaerobic bacteria that tend to grow in both open and closed wounds. Application of oxygen to wounds under pressure is known in the art as hyperbaric treatment. It has been shown that varying the pressure of such oxygen treatment, increases blood circulation in the treated area. This has the added advantage of pumping the patient's blood to the extremity such that the patient's own white blood cells are better able to assist in treatment of the microbes present in the wound or sore.
There are generally two broad general categories of devices for administering hyperbaric oxygen to a patient. The first category includes larger devices designed to enclose a patient's entire body or large portion of a patient's body, for example, both of the lower extremities of a patient. A second category of devices includes smaller, portable devices, which are known in the art as topical hyperbaric chambers and enclose a local region of the patient's body such as a single leg or a single arm.
There are several different devices used to apply topical oxygen to a patient's open wounds or sores. Certain existing hyperbaric oxygen devices include a rigid plastic enclosure that proves a pure oxygen atmosphere around the wound. Another characteristic of certain existing devices is that the oxygen is applied at a pressure greater than ambient pressure up to a maximum allowable level of fifty millimeters of mercury above ambient pressure. In one type of device, oxygen is applied to an entire extremity, for example, a leg having a wound or sore on a portion of the leg.
Various topical hyperbaric devices utilize a flexible bag designed to cover an entire leg or other extremity. Typically, these disposable hyperbaric oxygen chambers include a polyethylene bag which is substantially the length of the patient's leg, and tape is used at the top of the bag to seal the chamber around the upper thigh. Some hyperbaric oxygen chambers are in the form of an inflatable single layer bag, in which the pressure of oxygen is pulsated between minimum and maximum values, however, a disadvantage associated with a single layer bag is that during pulsated delivery of oxygen, the bag has a tendency to collapse when the pressure is reduced in the bag. Collapse of the bag poses the risk of the bag contacting the wound on the treated extremity. It would be desirable to provide a hyperbaric oxygen chamber that could be used to treat a single extremity and does not collapse when the pressure of the oxygen in the bag is reduced during pulsated delivery therein.